"Fast Fourier Transform of a Step-function in 3-dimonsional" please help me.

[fatemeh.mirjani]

Dear all;

I need a subroutine of Fortran90 about "Fast Fourier Transform of a Step-function in 3-dimonsional."
I read the related subroutines in Numerical Recipes Book, but I couldn't match it for a 3D step function.
Whould you please let me to have access to a subroutine for mentioned goal?

I'm anxiously looking forward your reply.

Kind Regards,
Fatemeh
 

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|Fatemeh Mirjani                              | Email: f_mirjani@ph.iut.ac.ir  |
|Computational Condensed Matter Research Lab. | Tel/Fax Office: +98311-3913746 |
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